Parser; Partial C++20 support, explicit(bool)

lib/templatesimplifier.cpp

@@ -3693,6 +3693,16 @@ void TemplateSimplifier::simplifyTemplates(
             if (end)
                 Token::eraseTokens(tok, end);
         }
+
+        // explicit(bool)
+        for (Token *tok = mTokenList.front(); tok; tok = tok->next()) {
+            if (Token::Match(tok, "explicit (")) {
+                bool isFalse = Token::simpleMatch(tok->tokAt(2), "false )");
+                Token::eraseTokens(tok, tok->linkAt(1)->next());
+                if (isFalse)
+                    tok->deleteThis();
+            }
+        }
     }
 
     mTokenizer->calculateScopes();

test/testsimplifytemplate.cpp

@@ -295,6 +295,9 @@ private:
         TEST_CASE(requires3);
         TEST_CASE(requires4);
         TEST_CASE(requires5);
+
+        TEST_CASE(explicitBool1);
+        TEST_CASE(explicitBool2);
     }
 
     std::string tok(const char code[], bool debugwarnings = false, Settings::PlatformType type = Settings::Native) {
@@ -6146,6 +6149,20 @@ private:
         const char expected[] = "int add<int> ( int a , int b ) ; add<int> ( 123 , 456 ) ; int add<int> ( int a , int b ) { return a + b ; }";
         ASSERT_EQUALS(expected, tok(code));
     }
+
+    void explicitBool1() {
+        Settings settings;
+        settings.standards.cpp = Standards::CPP20;
+        const char code[] = "class Fred { explicit(true) Fred(int); };";
+        ASSERT_EQUALS("class Fred { explicit Fred ( int ) ; } ;", tok(code));
+    }
+
+    void explicitBool2() {
+        Settings settings;
+        settings.standards.cpp = Standards::CPP20;
+        const char code[] = "class Fred { explicit(false) Fred(int); };";
+        ASSERT_EQUALS("class Fred { Fred ( int ) ; } ;", tok(code));
+    }
 };
 
 REGISTER_TEST(TestSimplifyTemplate)